/* ========================================
   Design System & CSS Variables
   ======================================== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
  /* Color Palette - Modern & Vibrant */
  --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --success-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --error-gradient: linear-gradient(135deg, #fa709a 0%, #fee140 100%);

  --bg-primary: #0a0e27;
  --bg-secondary: #151932;
  --bg-tertiary: #1e2442;
  --bg-glass: rgba(255, 255, 255, 0.05);
  --bg-glass-hover: rgba(255, 255, 255, 0.08);

  --text-primary: #ffffff;
  --text-secondary: #a0aec0;
  --text-muted: #718096;

  --border-color: rgba(255, 255, 255, 0.1);
  --border-active: rgba(102, 126, 234, 0.5);

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;

  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 40px rgba(102, 126, 234, 0.3);

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* ========================================
   Reset & Base Styles
   ======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* Animated Background */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 20% 50%, rgba(102, 126, 234, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(240, 147, 251, 0.1) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

/* ========================================
   Layout Container
   ======================================== */
.container {
  position: relative;
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-lg);
  z-index: 1;
}

/* ========================================
   Header
   ======================================== */
.header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  padding-top: var(--spacing-lg);
}

.header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--spacing-sm);
  animation: fadeInDown 0.6s ease;
}

.header p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  animation: fadeInUp 0.6s ease;
}

/* ========================================
   Progress Stepper
   ======================================== */
.progress-stepper {
  display: flex;
  justify-content: space-between;
  margin-bottom: var(--spacing-xl);
  position: relative;
  animation: fadeIn 0.8s ease;
}

.progress-stepper::before {
  content: '';
  position: absolute;
  top: 20px;
  left: 25%;
  right: 25%;
  height: 2px;
  background: var(--border-color);
  z-index: 0;
}

.step {
  position: relative;
  flex: 1;
  text-align: center;
  z-index: 1;
}

.step-number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 2px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--spacing-xs);
  font-weight: 600;
  transition: all var(--transition-base);
}

.step.active .step-number {
  background: var(--primary-gradient);
  border-color: transparent;
  box-shadow: var(--shadow-glow);
  transform: scale(1.1);
}

.step.completed .step-number {
  background: var(--success-gradient);
  border-color: transparent;
}

.step-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color var(--transition-base);
}

.step.active .step-label {
  color: var(--text-primary);
  font-weight: 500;
}

/* ========================================
   Form Container
   ======================================== */
.form-container {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
  animation: slideInUp 0.6s ease;
}

.form-step {
  display: none;
  animation: fadeIn 0.4s ease;
}

.form-step.active {
  display: block;
}

.step-title {
  font-size: 1.8rem;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.step-description {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  font-size: 0.95rem;
}

/* ========================================
   Form Elements
   ======================================== */
.form-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
}

.form-grid.two-columns {
  grid-template-columns: repeat(2, 1fr);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.form-group label {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 0.875rem 1rem;
  background: var(--bg-secondary);
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: 'Inter', sans-serif;
  transition: all var(--transition-base);
  outline: none;
}

.form-group input:focus,
.form-group select:focus {
  border-color: var(--border-active);
  background: var(--bg-tertiary);
  box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
}

.form-group input:focus+label,
.form-group input:not(:placeholder-shown)+label {
  color: var(--text-primary);
}

/* File Upload */
.file-upload-wrapper {
  position: relative;
}

.file-upload {
  display: none;
}

.file-upload-label {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-lg);
  background: var(--bg-secondary);
  border: 2px dashed var(--border-color);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  min-height: 120px;
}

.file-upload-label:hover {
  border-color: var(--border-active);
  background: var(--bg-glass-hover);
}

.file-upload-icon {
  font-size: 2rem;
  margin-bottom: var(--spacing-xs);
}

.file-upload-text {
  color: var(--text-secondary);
  font-size: 0.9rem;
  text-align: center;
}

.file-preview {
  margin-top: var(--spacing-sm);
  padding: var(--spacing-sm);
  background: var(--bg-tertiary);
  border-radius: var(--radius-sm);
  display: none;
  align-items: center;
  gap: var(--spacing-sm);
}

.file-preview.active {
  display: flex;
}

.file-preview-name {
  flex: 1;
  color: var(--text-primary);
  font-size: 0.9rem;
}

.file-preview-remove {
  background: var(--error-gradient);
  border: none;
  color: white;
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.85rem;
  transition: transform var(--transition-fast);
}

.file-preview-remove:hover {
  transform: scale(1.05);
}

/* ========================================
   Buttons
   ======================================== */
.form-buttons {
  display: flex;
  gap: var(--spacing-md);
  margin-top: var(--spacing-xl);
}

.btn {
  flex: 1;
  padding: 1rem 2rem;
  border: none;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  font-family: 'Inter', sans-serif;
  cursor: pointer;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.1);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

.btn-primary {
  background: var(--primary-gradient);
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 2px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-tertiary);
  border-color: var(--border-active);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

/* ========================================
   Modal/Popup
   ======================================== */
.modal-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(5px);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  animation: fadeIn var(--transition-base);
}

.modal-overlay.active {
  display: flex;
}

.modal {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  max-width: 500px;
  width: 90%;
  box-shadow: var(--shadow-lg);
  animation: scaleIn 0.4s ease;
  position: relative;
}

.modal-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto var(--spacing-md);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
}

.modal.success .modal-icon {
  background: var(--success-gradient);
}

.modal.error .modal-icon {
  background: var(--error-gradient);
}

.modal-title {
  font-size: 1.8rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--spacing-sm);
}

.modal.success .modal-title {
  background: var(--success-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.modal.error .modal-title {
  background: var(--error-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.modal-message {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  line-height: 1.6;
}

.modal-close {
  width: 100%;
  padding: 1rem;
  background: var(--primary-gradient);
  border: none;
  border-radius: var(--radius-md);
  color: white;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform var(--transition-base);
}

.modal-close:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

/* ========================================
   Animations
   ======================================== */
@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }

  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 768px) {
  .header h1 {
    font-size: 2rem;
  }

  .form-grid.two-columns {
    grid-template-columns: 1fr;
  }

  .progress-stepper {
    flex-wrap: wrap;
  }

  .step-label {
    font-size: 0.75rem;
  }

  .form-container {
    padding: var(--spacing-lg);
  }

  .form-buttons {
    flex-direction: column;
  }

  .container {
    padding: var(--spacing-md);
  }
}

@media (max-width: 480px) {
  .header h1 {
    font-size: 1.75rem;
  }

  .step-number {
    width: 35px;
    height: 35px;
    font-size: 0.9rem;
  }

  .step-label {
    display: none;
  }
}

/* ========================================
   Error States
   ======================================== */
.form-group.error input,
.form-group.error select {
  border-color: #fa709a;
}

.error-message {
  color: #fa709a;
  font-size: 0.85rem;
  margin-top: 0.25rem;
  display: none;
}

.form-group.error .error-message {
  display: block;
}

/* ========================================
   Loading State
   ======================================== */
.btn.loading {
  pointer-events: none;
  position: relative;
  color: transparent;
}

.btn.loading::after {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  top: 50%;
  left: 50%;
  margin-left: -10px;
  margin-top: -10px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ========================================
   OCR Result Display Styles
   ======================================== */
.ocr-result {
  display: none;
  margin-top: var(--spacing-md);
  animation: slideInUp 0.4s ease;
}

.ocr-result.active {
  display: block;
}

/* OCR Loading State */
.ocr-loading {
  text-align: center;
  padding: var(--spacing-lg);
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  border: 2px solid var(--border-color);
}

.ocr-loading .spinner {
  width: 40px;
  height: 40px;
  margin: 0 auto var(--spacing-sm);
  border: 4px solid rgba(102, 126, 234, 0.2);
  border-top-color: #667eea;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.ocr-loading p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin: 0;
}

/* OCR Success Result Card */
.ocr-result-card {
  background: var(--bg-secondary);
  border: 2px solid rgba(76, 175, 80, 0.3);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  animation: scaleIn 0.3s ease;
}

.ocr-result-card h4 {
  color: #4caf50;
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.ocr-data {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.ocr-field {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-xs);
  background: var(--bg-tertiary);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
}

.ocr-field span {
  color: var(--text-secondary);
}

.ocr-field strong {
  color: var(--text-primary);
  font-weight: 500;
}

/* OCR Error Card */
.ocr-error-card {
  background: var(--bg-secondary);
  border: 2px solid rgba(250, 112, 154, 0.3);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  text-align: center;
  animation: scaleIn 0.3s ease;
}

.ocr-error-card h4 {
  color: #fa709a;
  font-size: 1rem;
  margin-bottom: var(--spacing-xs);
}

.ocr-error-card p {
  color: var(--text-secondary);
  margin: var(--spacing-xs) 0;
}

.ocr-error-card small {
  color: var(--text-muted);
  font-size: 0. 85rem;
}

/* Comparison View Styles (for Step 4) */
.comparison-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}

.comparison-column {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
}

.comparison-column h3 {
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.comparison-item {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
  padding: var(--spacing-sm);
  background: var(--bg-tertiary);
  border-radius: var(--radius-sm);
  margin-bottom: var(--spacing-xs);
}

.comparison-item label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.comparison-item .value {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 500;
}

.match-indicator {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-right: var(--spacing-xs);
}

.match-indicator.match {
  background: #4caf50;
}

.match-indicator.mismatch {
  background: #fa709a;
}

/* Responsive OCR Results */
@media (max-width: 768px) {
  .comparison-grid {
    grid-template-columns: 1fr;
  }

  .ocr-field {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.25rem;
  }
}